16g BOTAl^T. 



leaves ovate in outline, 1-1 J' long, minutely strigose, bipinnatifid, the seg- 

 • ments oblong or linear ; heads in panicled racemes ; fertile ones with sev- 

 eral strong flattened prickles ; sterile ones vs^ith a 5-8-cleft involucre and 

 10-20 flowers; chafF of the sterile receptacle small and inconspicuous.— An 

 unsightly weed. Saskatchewan to Cahfornia, and eastward to Colorado and 

 New Mexico ; Steamboat Springs, Nevada, (Bloomer.) From the Sierras 

 to Great Salt Lake ; 4-6,000 feet elevation ; August-October. (591.) 



-Hymenoclea^ monogyea, T. & G. PI. Fendl., p. 79. Leaves 1-2' 

 long, entire or with a few distant divisions, the divisions, like the leaves, 

 filiform ; fertile involucres turbinate-fusiform, bearing near the middle a sin- 

 gle whorl of broadly obovate scales ; the apex tubular and moderately elon- 

 gated. — Plant 2-5° high, having the look of an Artemisia; the ripened fruit 

 silvery-scarious. California to New Mexico and Sonora. Foot-hills of Vir- 

 ginia Mountains, near the Truckee River ; 4,500 feet altitude ; May. (592.) 

 Xanthium steumakium, L., Var. echinatum, Grray. Manual, ed. 5, p. 

 252. Atlantic coast, and along the Glreat Lakes ; New Mexico and Califor- 

 nia. Truckee bottom, Nevada, and Promontory range, Utah ; 4,500-5,500 

 feet elevation ; July-October. (593.) 



Wyethia^ amplexicaulis, Nutt. Smooth throughout and glutinous or 

 resinous ; stems 1-2° high from a stout but scarcely woody root, leafy, 

 usually bearing 3-5 heads ; leaves broadly oblong-lanceolate, entire or serru- 

 late ; the radical ones often l°long and 2-3' broad, petioled ; the cauline 

 successively smaller, sessile, often somewhat clasping ; involucre 9-15" broad, 

 the glabrous subequal scales as long as the disk, the outer ones oblong, 



> HYMENOCLEA, T. & G., I. c. Heads of two sorts, clustered in the axils of the upper leaves, the 

 fertile ones helow the sterile. Fertile heads with an ohoToid closed coriaceous one-celled and one-flow- 

 ered involucre, which when mature has the sides winged with a circle or spiral of broad scarious append- 

 ages, representing the dilated tips of the involucral scales, the apex of the involucre conical, tubular, 

 pointed. Sterile heads 5-6-lobed, 15-20-flowered ; the receptacle small, bearing small obovate or spatu- 

 late clawed scarious chaff, nearly as long as the funnel-shaped or goblet-shaped 5-toothed corolla ; an- 

 thers with a small inflexed deltoid appendage. — Glabrous much-branched shrubby plants, with alternate 

 filiform leaves, or the lower ones pinnately 3-5-divided. Genus of two species only, natives of Califor- 

 nia, Nevada, Arizona, New Mexico, &c. 



2 WYETHIA, Nu'iT. Heads many-flowered, radiate ; the rays very large, pistillate, fertile ; disk- 

 flowers numerous, tubular, ampliated near the base, five-toothed. Scales of the Campanulate involucre 

 imbricated in 2-3 series, subequal, the outer ones equaling or exceeding the dish, foliaceous, the inner 

 ones narrow and rigid. Eeceptacle slightly convex, the lanceolate acuminate carinate ohartaoeous 

 chaff as long as the disk-flowers and slightly inclosing them. Branches of the style of the disk-flowers 

 linear-elongated, recurved, hispid, of the ray glabrous. Achenia elongated, flattened, somewhat 4-5-an- 

 gled and prismatic, mostly smooth. Pappus coroniform, rigid, the teeth short and erose or denticulated, 

 one or more of them often produced into awns. — Coarse perennial herbs, often resinous or balsamic, with 

 ample nearly entire leaves, and large sunflower-like yellow heads, either solitary and terminal, or few 

 on axillary peduncles ; natives of North America from Oregon to New Mexico. 



